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141.
M Valente U Bortolotti G Thiene E Arbustini A Milano A Mazzucco V Gallucci 《European journal of cardio-thoracic surgery》1987,1(3):134-138
The occurrence of stent post deformity was investigated in 38 consecutive, polypropylene flexible-stented Hancock porcine bioprostheses (PB) recovered from the mitral position because of early postoperative death or late tissue failure. The degree of deformity was assessed for each explant by calculating the triangular area obtained by projecting the apex of the stent posts on a plane and comparing it with the same area calculated for unimplanted PBs of comparable size. A significant stent deformity (reduction of the triangular area greater than 40%) was observed only in 6 PBs explanted because of tissue failure after a mean function time of 69.6 +/- 28 months. In these PBs, scanning electron microscopy of the bare surface of the stent at the point of maximal flexion showed cracks 0.7-1 microns large, which represent the morphological substrate of the so-called "creep" of polypropylene. Inward stent post bending may occur after implantation in mitral PBs and when severe, it corresponds to a definite ultrastructural plastic deformity of polypropylene. 相似文献
142.
Summary In the guinea-pig terminal ileum a maximally effective concentration of prostacyclin (PGI2) (1 ol/l) induced contractions that were partially resistant to tetrodotoxin (TTX) 0.1 mol/l, to low temperature (20°C) and to atropine (30 nmol/l). Half maximum contractions evoked by PGI2 (20 nmol/l) were abolished by TTX and by low temperature, which did not modify the response to exogenous acetylcholine (ACh), as well as by atropine. Procaine (5–500 ol/l) caused a concentration-dependent inhibition of contractions induced by PGI2 (20 nmol/l and 1 mol/l) and by equieffective concentrations of ACh (20 nmol/l and 0.4 ol/l, respectively). The order of magnitude for this inhibition was ACh 20 nmol/l = PGI2 20 nmol/l > PGI21 mol/l > ACh 0.4 mol/l. In preparations exposed to TTX or to low temperature procaine (50 mol/l) did not affect the residual response to PGI2 (1 mol/l). Quercetin (1 and 5 ol/l) inhibited the effect of PGI2 and, at higher concentrations, it also caused partial depression of the responses to ACh. Quercetin did not alter TTX-resistant and low temperature-resistant contractions induced by PGI2 1 mol/l. Carbonyl cyanide-trifluoromethoxyphenyl hydrazone (FCCP) (0.1–1 ol/l) reduced the effect of PGI2 and of ACh to approximately the same extent and inhibited the residual response to PGI2 1 mol/l in preparations treated with TTX or expressed to low temperature. The present results show that PGI2, besides acting on cholinergic neurons, also exerts a direct effect on smooth muscle cells and FCCP can be used to block this effect. In contrast procaine and quercetin selectively inhibit the ACh-mediated component of PGI2 action.
Send offprint requests to R. M. Gaion 相似文献
143.
Musculoskeletal sarcomas are rare cancers with an incidence of less than 1% of all cancers. Management of these tumors requires multidisciplinary care comprising of numerous specialists. Critical decisions following collaborative discussion among treating specialists followed by timely communication and starting prompt treatment are vital in delivering care in such rare sarcomas. While musculoskeletal surgeons, radiologists, and clinical oncologists are well known, the role of specialist nurses has been less described. They form a vital pillar in any tertiary sarcoma service by assisting in collaborative care, having consultations in nurse-led clinics, offering psychological support, imparting details of treatment to patient and helping in palliative care. This narrative review focuses on the role of trained specialist nurses in a tertiary sarcoma service and gives insight into their vital role in delivering timely, coordinated, effective care. 相似文献
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146.
Capovilla Giovanni Moletta Lucia Pierobon Elisa Sefora Salvador Renato Provenzano Luca Zanchettin Gianpietro Costantini Mario Merigliano Stefano Valmasoni Michele 《Annals of surgical oncology》2021,28(3):476-476
Annals of Surgical Oncology - 相似文献
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148.
Archives of Sexual Behavior - Men with light eyes lack the dominant gene allele that codes for dark-brown eyes. Pairing with a woman who lacks the same allele must increase paternity confidence in... 相似文献
149.
《Health policy (Amsterdam, Netherlands)》2021,125(12):1527-1535
Obesity and overweight conditions have become major health challenges worldwide. The exploration of effective weight loss strategies is essential. Nudges are currently advancing approaches that represent a new and better method for changing the behaviors of people. However, the effectiveness of nudge interventions on weight loss in overweight people who may be obese has not been synthesized in a systematic manner. In this study, a systematic literature search was performed. Only randomized controlled trials (RCTs) were considered. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated as summary statistics. In total, 25 RCTs involving a population of 5,929 individuals were included. Significant effects of the nudge strategy on weight loss (WMD: -0.96 kg, 95% CI: -1.49 to -0.43), body mass index (WMD: -0.3 kg/m2, 95% CI: -0.41 to -0.19) and waist circumference (WMD: -0.75 cm, 95% CI: -1.23 to -0.27) were observed. The subgroup analysis showed that the reduction in body weight associated with nudge interventions was significant in younger and more obese people. Moreover, the effect of nudge intervention on weight loss weakened over time. Overall, the nudge strategy can promote changes in weight loss, body mass index and waist circumference of adults, albeit at a mild magnitude and in particular types of individuals. Nudge strategies can be recommended to clinical practitioners and policy-makers to promote obesity management. 相似文献
150.
《Health policy (Amsterdam, Netherlands)》2021,125(10):1359-1366
In this article, the associations among individual socio-economic characteristics, the institutional set-up of health care systems, and satisfaction with the health care system are investigated. Data from the 2011 International Social Survey Program (30 countries, 34,212 respondents) is used. Multilevel analyses across countries have shown how the state financing context affects satisfaction at the individual level. Consistent with previous research, at individual level, personal experiences with medical providers, age, gender as well as income are significant predictors of satisfaction with the health care system. At the country level, real input indicators such as density of physicians and density of hospital beds are negative predictors of satisfaction with the health care system whereas the percentage of total health expenditures comprised by public sources is a positive predictor of satisfaction with the health care system. However, findings from the cross-level interactions indicate that the negative effect of lower income is more prominent in predominantly publicly-funded health care systems. Specifically, in primarily publicly-funded health care systems, the model-predicted probability of satisfaction with the health care system is higher, but the gap in the probability of satisfaction with the health care system between individuals with lower income and those with higher income is greater than that in mostly privately-financed health care systems. The findings in this study suggest that the future direction of health care system reform should be focused on balancing the distribution of resources between private and public sectors. 相似文献